NEW YORK, Aug 1 (Reuters) - A rush of unusually high volume
ripped through dozens of stocks on the New York Stock Exchange
in early trading on Wednesday due to a technology error at
market maker Knight Capital, becoming the latest in a series of
high-profile mishaps that have damaged investor confidence in
public markets.

Heavy computer-based trading erupted at the open, diverting
attention from the day's news, and prompting the NYSE to review
trades in 140 different issues after the issue caused a trading
halt in a handful of New York Stock Exchange-listed stocks.

"This morning, a technology issue occurred in Knight’s
market-making unit related to the routing of shares of
approximately 150 stocks to the NYSE," Knight Capital (KCG.N),
one of the largest U.S. market makers, said in a statement.

Knight said the problem prompted it to tell clients to send
orders to other firms. Knight officials were not available for
further comment.

As a market maker, Knight stands ready to buy and sell
shares at quoted prices, adding to market liquidity.

The trading glitches follow a series of events that have
hurt retail investors' confidence in the market, including the
botched Facebook initial public offering, the 2010 "flash
crash," and the failed public offering of BATS Global Markets.

On Wednesday, a surge of orders were executed at the start
of trading, disrupting normal trading activity.

Several market participants said the source of the problem
may have been large orders meant to be filled throughout the day
that were instead executed in a shorter time frame, with some
saying the orders came in the first 15 minutes of trading.

The broader market was little changed, with the Standard &
Poor's 500 index .SPX .INX up 0.25 percent, as the trading
glitch quickly became the focus for traders.

"That has disrupted all the normal activities - stocks are
moving all over the place, they are weird, they are trading like
millions of shares, 100 shares at a time, so something went
haywire somewhere," Stephen Massocca, managing director, Wedbush
Morgan in San Francisco, said in the first hour of trading.

Shares of Knight Capital plunged 21.4 percent to $8.13,
after hitting a seven-year low of $7.60 a share.

It was unclear whether the problem was related to NYSE's new
program, launched on Wednesday, that gives retail traders
slightly better prices than others in the market.
[ID:nL2E8I5C4N]

The program is seen as an effort to induce retail investors
to trade away from mostly off-exchange electronic "wholesalers."

The NYSE's Retail Liquidity Program is a direct challenge to
Knight and other market makers that typically get a first look
at the highly coveted orders from individual traders, known as
retailers, and it is meant to reclaim some market share NYSE
lost over the last decade.

A spokesperson for NYSE Euronext NYX.N declined to
comment, but a source familiar with the matter said the exchange
had not experienced any issues with its systems.

"It appears to be dozens if not hundreds of stocks that have

(seen) extremely high volume and extremely rapid movement," said
Joe Saluzzi, co-manager of trading at Themis Trading in Chatham,
New Jersey.

Trading in those names was much heavier than normal.
Molycorp traded more than 5.7 million shares in the first 45
minutes of trading. The stock usually averages about 2.65
million shares daily, and it was one of the stocks halted due to
excessive volatility. The stock traded between a range of $17.50
and $14.35 on the session.

Unusual volume was seen in a disparate group of stocks,
including Lithia Motors (LAD.N), which already had seen trading
volume of 4.3 million shares. The stock usually trades about
95,000 shares daily.

Among other stocks, Protective Life PL.N had already
traded more than 10 times its usual volume, and Juniper Networks
JPNR.N has already seen six times its usual daily volume.

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